Vitamin K Prophylaxis for Preterm Infants: A Randomized, Controlled Trial of 3 Regimens

Abstract

Vitamin K1 prophylaxis with 0.2 mg administered intramuscularly maintained adequate vitamin K status of preterm infants until a median age of 25 postnatal days and did not cause early vitamin K1 2,3-epoxide accumulation. In contrast, 0.2 mg administered intravenously and 0.5 mg administered intramuscularly led to vitamin K1 2,3-epoxide accumulation, possibly indicating overload of the immature liver. To protect against late vitamin K1 deficiency bleeding, breastfed preterm infants given a 0.2-mg dose of prophylaxis should receive additional supplementation when feeding has been established.

Urinary Excretion of Vitamin K Metabolites in Term and Preterm Infants: Relationship to Vitamin K Status and Prophylaxis

“…However, it does not discount that low urinary output may also reflect an immaturity of the enzymic pathway leading to vitamin K catabolism. Despite the low liver stores at birth, detectable circulatory levels of PIVKA-II are present only in a minority of newborns (6,8,20). PIVKA-II was undetectable in all preterm infants in this study showed that their vitamin K status was sufficient for the efficient functional ␥-carboxylation of hepatic coagulation factors.…”

“…This pattern may indicate saturation of a component(s) of the -and ␤-oxidative enzyme system that carries out degradative side chain shortening of vitamin K before excretion (18,19). The likelihood that some preterm infants are unable to efficiently metabolize current prophylactic doses of vitamin K given at birth is supported by the finding that many preterms in this trial still had grossly elevated circulatory levels of K 1 on the fifth day of life that reached concentrations to several 100-fold higher than endogenous concentrations in healthy adults (20). These finding are consistent with previous reports (11,12).…”

“…Preterm infants were eligible to participate in this study if admitted to the Neonatal Intensive Care Unit at Hope Hospital between December 2002 and October 2003 after delivery at Ͻ32 wk gestation. They comprised a subgroup of infants enrolled into a clinical trial comparing vitamin K status of preterm infants after three regimens of prophylaxis (20). The same exclusion criteria applied as for the term infants.…”

“…Infants were randomly allocated to receive one of the following doses of Konakion Neonatal vitamin K 1 : 200 g i.m., 500 g i.m., or 200 g i.v. Because preterm infants are potentially at increased risk of VKDB (13,20), vitamin K prophylaxis was not delayed. We aimed to collect all urine voided in the first week of life, but at least for 48 h after vitamin K 1 administration.…”

Vitamin K Prophylaxis in Infants

“…Health care professionals should promote awareness among families of the risk of late VKDB associated with inadequate vitamin K prophylaxis from current oral dosage regimens, particularly for newborns who are breastfed exclusively 1,4 .…”